Oil and gas will play a central role in the global energy system for the foreseeable future. However, uncertainty surrounds both the availability of and demand for these fuels, and as a result, there are quite disparate viewpoints on the magnitude of this role. The aim of this thesis is to identify, understand, quantify and, where possible, minimise the sources of this uncertainty, and to investigate the implications that such uncertainties have on the future of oil and gas. There are two areas of original contribution to knowledge. First, while numerous studies have examined the availability of various subsets of oil and gas, often in a deterministic manner, this work provides a full description of the uncertainty in the resource potential of all individual categories of oil and gas. This includes estimating the uncertainty in resource availability at different costs of production, and also examining the resource potential of categories that have been previously overlooked. Second, the implications of this and other major sources of uncertainty have never been investigated using models that incorporate both supply and demand-side dynamics. Two models are used for this purpose. The first is an existing energy systems model, TIAM-UCL, which has been substantially modified to allow a more accurate characterisation of long-term oil and gas production and consumption. The second is an oil-sector specific model that has been developed named the 'Bottom-Up Geological and Economic Oil field production model' (BUEGO). This is capable of examining oil production potential to 2035 and is used to examine shorter-term and more sector specific uncertainties.

Living in a cold, damp home is harmful to physical and mental health. Household energy efficiency measures, often installed to reduce carbon emissions, should make it easier and more affordable for residents to maintain a warm, comfortable environment, thereby reducing cold-related illnesses and associated stress. However, the expected health benefits are often not seen and concerns have been raised of unplanned, detrimental effects on health. A series of studies was conducted to investigate the relationship between household energy efficiency measures and the health of residents using three different approaches. Initially, the mechanisms by which such health benefits may be achieved were investigated via continuous indoor environmental monitoring in a number of case study homes and a questionnaire-based survey of residents following a council retrofit scheme. A meta-analysis of the extant evidence then identified a positive impact from household energy efficiency measures on health. Finally, professionals involved in the planning or implementation of household energy efficiency schemes were interviewed to determine the extent to which health is considered in organisational and individual objectives. The present research contributes to the design of effective energy efficiency policies and interventions. The presence of household energy efficiency measures was found to have a positive effect on health on average, particularly for residents vulnerable to the impacts of fuel poverty due to their age, health or income. Physical and perceived changes to the home environment were identified as the key consecutive components of the mechanism for this effect. Future research that comprehensively assesses long-term health impacts alongside short-term changes in wellbeing would contribute to the promotion of household energy efficiency measures. The need was recognised, though, for a holistic, collaborative approach to address individual needs and overcome institutional barriers in order to achieve concurrent environmental, economic, social and health benefits.

In this work we propose a term structure power price model that, in contrast to widely accepted no-arbitrage based approaches, accounts for the non-storable nature of power. It belongs to a class of equilibrium game-theoretic models with players divided into producers and consumers. Consumers aim to maximize a mean-variance utility function subject to the inelastic demand of their own clients (households, businesses etc.) to whom they sell power. Similarly, producers, who own a portfolio of power plants each defined by a running fuel (gas, coal, oil etc.) and various physical characteristics (efficiency, capacity, ramp up/down times etc.), seek to maximize a mean-variance utility function consisting of power, fuel, and emission prices subject to production constraints. Our goal is to determine the term structure of the power price at which production matches consumption. In this work we show that in such a setting, the equilibrium price exists, and also discuss conditions under which it is unique. We then extend the model to incorporate information about block contracts, transaction costs and liquidity. Moreover, we propose a tractable quadratic programming formulation for calculating the equilibrium term structure of electricity prices. Our numerical simulations examine the dependence of the term structure on various parameters of the model. Our model is applied to calculate the equilibrium term structure of electricity prices in the UK, by modeling the entire power grid consisting of a few hundred power plants. We extend the model further by modeling startup costs of power plants. In contrast to other approaches presented in the literature, we incorporate them in a mathematically rigorous manner without relying on ad hoc heuristics. We propose a tractable approach for estimating startup costs of power plants based on their historical production. Through numerical simulations applied to the entire UK power grid, we demonstrate that the inclusion of startup costs is necessary for modeling electricity prices in realistic power systems.

Examination of climate policies such as downstream cap-and-trade brings into sharp focus the tension between environmental and broader social policy aims. This is particularly true in the residential energy sector. Here, policies to reduce general levels of greenhouse gas emissions must be reconciled with ensuring the affordability of energy for vulnerable consumers. This thesis examines the practical application of justice concerns at the nexus of environmental and social policy, specifically in the domain of household energy demand. To tackle issues of justice in this context an understanding of sufficiency is required: the moral distinction between under- and over-consumption. This thesis presents the application of two theories to understand this notion: first, a ‘needs’ interpretation of household energy as a requirement to support wellbeing; and second, a ‘capabilities’ approach for understanding the opportunities and constraints of households in responding to policy incentives. Further, microsimulation modelling provides a comparative analysis of the potential impact on households using different interpretations of justice. The contribution made is the application and integration of a theoretically grounded understanding of justice to the empirical context of household energy demand reduction. A framework is described within which the moral dimension of policy decisions are made more explicit. Thus, policy-makers are provided with a decision-support tool with which to approach energy related justice concerns. More specifically, the findings will be relevant for the public acceptability and political feasibility of downstream carbon trading schemes.

As significant energy consumers, UK households need to reduce their energy use if the UK is to achieve its greenhouse gas reduction targets. Low levels of engagement and adoption rates of energy curtailment measures need to be overcome. Policies perceived as ‘fair’ can increase levels of engagement and acceptability. This thesis explores how households approach reducing their own energy use, the reductions they can achieve and any existing barriers. Households’ perception of what is ‘fair’ in the context of energy reductions is explored based on households' own experiences of energy reduction. Households recruited from the South East of England participated in a mixed-methods study attempting to reduce their energy use over a 12-month period. Provided with estimates of their carbon footprints and a comparison to the UK average, the participants discussed their energy use, reductions and perceptions of how reductions could be encouraged fairly. Participants’ energy use was something of an enigma, as were the associated GHG emissions. However, its use was protected and seen as ‘acceptable’ and ‘necessary’ for them to be comfortable in their day-to-day lives. Reducing their energy use was seen as possible and acceptable in areas of energy use viewed as ‘wasteful’ or ‘unnecessary’. While seen as possible, these targets were not necessarily achievable, with 50 per cent of the participants making measurable reductions, and 50 per cent unable to. Energy reductions of ten per cent were seen as possible, even by those unable to reduce, with little scope to move beyond this as participants did not know what they should or could do next. To move forward participants viewed fairness as important, citing energy reductions needing to be a valid, legitimate aim of society; with required reductions being achievable, supported by information, and placing the burden of responsibility on those who use the most.

There is a growing need to curtail the carbon emissions in the globe in order to achieve the climate stabilisation goals based on the climate change threat. And as such, different initiatives and schemes of Government have targeted a number of policies at reducing energy and carbon emissions targets with the housing sector of the economy not an exception. In order to explore the feasibility of achieving carbon emissions reduction targets within the housing sector of the UK, the research views the issue of household energy consumption and carbon emissions as complex sociotechnical problem involving the analysis of both the social and technical variables. This thesis therefore describes the development of the system dynamics based model to capture and solve the problem relating to the future profiles of household energy consumption and carbon emissions by providing a policy advice tool for use by the policy makers. In order to investigate the problem, the research adopts the pragmatist research strategy involving collection of both qualitative and quantitative data to develop the model. The developed model has six modules, which are: population/household, dwelling internal heat, occupants’ thermal comfort, climatic-economic-energy efficiency interaction, household energy consumption, and household CO2 emissions. In addition to the ‘baseline’ scenario, the developed model was used to develop four illustrative scenarios of household energy consumption and carbon emissions; which are: ‘efficiency’ scenario, ‘behavioural change’ scenario, ‘economic’ scenario, and ‘integrated’ scenario. The ‘efficiency’ scenario generally considers the effects of improvements in energy efficiency measures on household energy consumption and ultimately on household carbon emissions. Additionally, the ‘behavioural change’ scenario tries to model the effects of occupants’ change of energy consumption behaviour on household energy consumption and carbon emissions profile. The ‘economic’ scenario assumes a case of policy change by Government favouring energy prices reduction, thereby reducing the energy bills payable by the householders and its consequences on household energy consumption and carbon emissions. And the ‘integrated’ scenario combines the assumptions in the first three scenarios and then analyses its effects on household energy consumption and carbon emissions. The ‘baseline’ results indicate that about 49% savings in carbon emissions by the year 2050 below the base year of 1990 are possible. Additionally, the results of the developed model for all the illustrative scenarios indicate that carbon emissions savings of 46%, 55%, 58%, and 63% below the base year of 1990 are possible from the ‘economic’, ‘efficiency’, ‘behavioural change’, and ‘integrated’ scenarios respectively. The research concludes that it is unlikely for any of the scenarios by its own to meet the required legally binding reductions of 80% cut in carbon emissions by 2050 unless this is vigorously pursued. The unique contribution of the research is the development of a model that incorporates socio-technical issues that can be used for decision making over time.

Reducing energy consumption in the Telecom industry has become a major research challenge to the Internet community due to high level of energy waste on redundant network devices. In search for a paradigm shift, recent research efforts have been focusing on time-driven sleep-mode reconfiguration of network elements during periods of low traffic demand. However, due to the routing re-convergence issue of today's traditional IP routing protocols, frequent network reconfigurations are generally deemed to be harmful as a result of routing table re-convergence. Furthermore, diurnal traffic behaviours are unpredictable and can lead to network congestion as a result of the reduced network resources. This thesis presents novel event-driven green backbone routing schemes for network managements which are capable of saving energy in fixed IP networks (using both regular and non-regular traffic matrix) without inhibiting its performance. First, a Link Wake-up Optimisation Technique (LiWOT) is proposed during energy saving periods when the pruned topology is applied. The key novelty here is that LiWOT selects the minimum number of router's line cards to wake-up when the network is congestion is detected. This is contrary to the norms of reverting to the full network topology or on-the-fly network reconfigurations in the case of even minor traffic surge and thereby sacrificing energy savings. In order to mitigate the effect of routing re-convergence in networks, LiWOT prioritises the waking up of non-disruptive sleeping links. This scheme was further extended to a fully disruption-free scheme. The second proposed scheme is the Green Link Weight Disruption-Free Energy-aware Traffic Engineering which limits its wake-up operation to only non-disruptive links. In order to maximise the energy savings, the number of this type of links are maximised in an offline manner. Using a genetic algorithm based approach, a new link weight optimisation scheme is proposed and this forms the basis of the second research contribution. Finally, a completely dynamic link sleeping reconfigurations (DLSR) for green traffic engineering is proposed. The scheme coordinates the sleep and wake-up operations in a dynamic way such that operations are based on the current traffic. The key contribution is that DLSR is oblivious of historical traffic conditions like the previous schemes and can enhance energy savings by putting back woken-up links to sleeping mode during low traffic. The performances of the three schemes were evaluated using the publicly accessible traffic traces of both GEANT and Abilene network respectively over a period of one week and the obtained results show a substantial amount of energy saving.

Energy efficiency regulations and standards are increasingly being used as an approach to reduce the impact of appliances on climate change. Each new generation of games consoles is significantly different to the last and their cumulative electricity use has risen due to improved performance and functionality and increasing sales. As a result, consoles have been identified in the EU, US and Australia as a product group with the potential for significant electricity savings. However, there is a good deal of uncertainty regarding cumulative electricity use of consoles as measurements of power consumption are crude and user behaviour poorly understood. In particular, due to the highly competitive nature of the games console market there is a lack of information available regarding product specifications and power consumption prior to launch. This has made it difficult for policy makers and other stakeholders to determine what is technically achievable in terms of potential electricity saving, and the role that energy efficiency regulations and standards can play, until a product launches. This research establishes robust estimates of console usage and measures the power consumption of each model of PlayStation® platform sold in Europe since 1995. These data are used to calculate both the electricity use per unit and the cumulative electricity use of each platform. Furthermore, a study of PlayStation®4 estimates the potential electricity saving that could be achieved using various efficiency improvements. The study shows that PlayStation®4 is likely to mitigate, and may even reverse, the trend of increasing electricity use between product generations due to the integration of energy efficient technologies from the initial stages of product design. The results of this research have been key to the European Commission establishing that the voluntary approach to reducing console electricity use proposed by console manufacturers is sufficiently robust and ambitious.

Every day each of us consumes a significant amount of energy, both directly through transport, heating and use of appliances, and indirectly from our needs for the production of food, manufacture of goods and provision of services. This dissertation investigates a personal energy meter which can record and apportion an individual's energy usage in order to supply baseline information and incentives for reducing our environmental impact. If the energy costs of large shared resources are split evenly without regard for individual consumption each person minimises his own losses by taking advantage of others. Context awareness offers the potential to change this balance and apportion energy costs to those who cause them to be incurred. This dissertation explores how sensor systems installed in many buildings today can be used to apportion energy consumption between users, including an evaluation of a range of strategies in a case study and elaboration of the overriding principles that are generally applicable. It also shows how second-order estimators combined with location data can provide a proxy for fine-grained sensing. A key ingredient for apportionment mechanisms is data on energy usage. This may come from metering devices or buildings directly, or from profiling devices and using secondary indicators to infer their power state. A mechanism for profiling devices to determine the energy costs of specific activities, particularly applicable to shared programmable devices is presented which can make this process simpler and more accurate. By combining crowdsourced building-inventory information and a simple building energy model it is possible to estimate an individual's energy use disaggregated by device class with very little directsensing. Contextual information provides crucial cues for apportioning the use and energy costs of resources, and one of the most valuable sources from which to infer context is location. A key ingredient for a personal energy meter is a low cost, low infrastructure location system that can be deployed on a truly global scale. This dissertation presents a description and evaluation of the new concept of inquiry-free Bluetooth tracking that has the potential to offer indoor location information with significantly less infrastructure and calibration than other systems. Finally, a suitable architecture for a personal energy meter on a global scale is demonstrated using a mobile phone application to aggregate energy feeds based on the case studies and technologies developed.

The past decade has seen a significant rise in the interest of deploying Marine Renewable Energy technologies. Tidal stream technology is developing rapidly, and developers are favouring horizontal axis turbines (HAT’s). However, vertical axis turbines (VAT’s) are better suited for shallow waters, and higher efficiencies can potentially be gained by utilising shallow water blockage effects. The Severn Estuary is an ideal deployment area in this context. Additionally, due to a large tidal range the estuary has long been the subject of tidal barrage proposals. The original ebb-only STPG barrage has recently been superseded by a two-way generation scheme, therefore the need exists for renewed research into the hydrodynamic impacts of this proposal. Furthermore, little is known about the interaction between tidal range and tidal stream technologies, and if they could coexist in the Severn Estuary. This thesis uses physical and numerical modelling techniques to assess a range of MRE technologies, with particular focus on their deployment in the Severn Estuary. Physical model tests of a number of VAT’s were conducted in a recirculating flume. Device performance and the wake characteristics were assessed, and it was demonstrated that VATS’s could potentially provide competitive performance values if deployed in shallow waters. The CFD code ANSYS CFX was used to predict the unsteady turbine behaviour at the physical model scale; good agreement was achieved with the laboratory data, particularly in predicting the wake behaviour. The CFD model TRIVAST was then applied to the Severn Estuary. Comparisons were made of the Severn Barrage schemes, as well as two hypothetical HAT and VAT arrays. The model results confirmed that vertical axis turbines are better suited to the Severn Estuary, provided that the technology is feasible. Finally, whilst the Severn Barrage proposals would eradicate the HAT resource, a lesser impact on the VAT resource was observed.